Macular pucker formation after inverted internal limiting membrane flap technique: Two case reports.

PURPOSE: The inverted internal limiting membrane (ILM) flap technique is generally used to treat refractory macular holes (MHs). Recently, a case of macular pucker formation outside the ILM flap after using silicone oil was reported. Although the pucker formation was attributed to the silicone oil use in that case, here we report two cases of macular pucker that occurred after the inverted ILM flap technique was performed without silicone oil. In one case, the ILM flap and proliferated tissue was removed, followed by their histopathological examination. OBSERVATIONS: Two patients with MH underwent vitrectomies using the inverted ILM flap technique. In both patients, the visual acuity worsened postoperatively, and macular pucker formation, associated with the ILM flap, was observed. In one patient, visual acuity improved after ILM flap removal, and histopathological examination of the specimen indicated strong cellular proliferation between the ILMs. CONCLUSIONS AND IMPORTANCE: Following the inverted ILM flap technique, macular pucker may occur even without the use of silicone oil. Removal of the flap and associated proliferative tissue was effective and resulted in no recurrence of MH or pucker. Ophthalmologists should consider the possibility that tissues on the ILM may lead to macular pucker formation especially inside the flap, in the area between the ILMs.

Safety and Efficacy of Cold Snare Polypectomy Without Submucosal Injection for Large Sessile Serrated Lesions: A Prospective Study.

BACKGROUND & AIMS: Cold snare polypectomy (CSP) has become the standard resection method for small colorectal polyps (<10 mm). Sessile serrated lesions (SSL) have low prevalence of advanced histology irrespective of size, and thus could be amenable to CSP. In this study, we evaluated the safety and efficacy of CSP for SSLs ≥10 mm. METHODS: Between November 2018 and January 2020, we prospectively enrolled 300 consecutive patients who underwent CSP for 474 SSLs ≥10 mm. To delineate SSL borders, indigo carmine chromoendoscopy and/or image-enhanced endoscopy was conducted. Piecemeal CSP (pCSP) was performed in cases where en-bloc resection was difficult. Biopsy specimens were obtained from the margins of the post-polypectomy defect to confirm complete resection. Surveillance colonoscopy was performed to screen for local recurrence. RESULTS: All lesions were successfully resected using CSP without submucosal injection. The median diameter of the resected lesions was 14 mm, and pCSP was used to resect 106 (22%) lesions. Post-polypectomy biopsies revealed residual serrated tissue in only one case (0.2%). Adverse events included immediate bleeding in 8 (3%) patients; no delayed bleeding events occurred, irrespective of the use of antithrombotic drugs. During a 7-month median follow-up period, surveillance colonoscopies were performed for 384 lesions (81%), and no local recurrences were detected. CONCLUSIONS: CSP without submucosal injection is a safe and effective treatment for SSLs ≥10 mm. UMIN Clinical Trials, Number: UMIN000034763.

New hemostatic technique with combined use of Hydrofit® and Surgicel®: an in vitro and in vivo study.

We developed an effective hemostatic technique using Hydrofit® and Surgicel® simultaneously. The aim of this study was to demonstrate the hemostatic efficacy of the Hydrofit® and Surgicel® combination technique through an in vitro experiment and to elucidate mid-term consequences of the combined components through an in vivo experiment. For the in vitro experiment, a closed circuit using a heparin-coated cardiopulmonary bypass circuit and a prosthetic graft was created. The amount of bleeding from the prosthetic graft was measured, and the following three hemostatic methods were applied: only gauze compression in control group, Hydrofit® application in Hydrofit group, Surgicel® spread Hydrofit® application in Hydrofit and Surgicel (HS) group, respectively. In the in vivo experiment, Hydrofit® and/or Surgicel® were implanted under skin on the back of rats (n = 10) at 4 points. In the control group, only an incision was made; in the Hydrofit, Surgicel, and HS groups, Hydrofit® and/or Surgicel® was implanted. One and three months later, each of the five rats were killed and in each section histopathologic examination was carried out. In the in vitro experiment, the amount of bleeding was 7.84 ± 1.08, 2.26 ± 1.02, and 0.87 ± 0.38 ml in the control, Hydrofit, and HS groups, respectively. The amount of bleeding in the HS group was more suppressed than in the Hydrofit group (p = 0.012). In the in vivo experiment, the maximal depth diameter of each remaining hemostatic sealant was measured. After 3 months, the diameter was 0, 2289.0 ± 768.2, 3850.3 ± 935.8 µm in Surgicel, Hydrofit and HS groups, respectively. The diameter was significantly increased in the HS group compared with the Surgicel and Hydrofit groups (p < 0.001, respectively,). In conclusion, the combination of Hydrofit® and Surgicel® was effective in achieving hemostasis. The remnants of Hydrofit® and Surgicel® were present for a long time in the tissues which could compress the surrounding tissue.

Risk factors of delayed bleeding after endoscopic resection of superficial non-ampullary duodenal epithelial tumors and prevention by over-the-scope and conventional clipping.

OBJECTIVES: This study was aimed to reveal risk factors for delayed bleeding after endoscopic resection (ER) of superficial non-ampullary duodenal epithelial tumors (SNADETs) and at exploring measures to prevent this complication. METHODS: A total of 235 consecutive patients with 249 SNADETs who had undergone ER were enrolled in this study. They were divided into two groups: OTSC group, consisting of the initial 114 cases in which the defects were closed only using OTSCs; and OTSC-c group, consisting of the later 135 cases in which conventional clips were additionally used to cover the inverted submucosa after post-procedure defect closure using OTSCs. The therapeutic outcomes were then compared between the OTSC and OTSC-c groups. RESULTS: All lesions were successfully resected en-bloc, and the R0 resection rate was 92.4%. The complete defect closure rate was 90.0% and no delayed perforation occurred when successful defect closure was achieved. The rate of delayed bleeding was significantly higher in the OTSC group than in OTSC-c group (11.4% vs. 1.5%, P = 0.001). Multivariate logistic regression analyses revealed that tumor location distal to the ampulla (OR 10.0; 95% CI 1.24-81.0, P = 0.03) and use of a DOAC (OR 8.83; 95% CI 1.13-68.7, P = 0.04) were significant independent predictors of delayed bleeding. Propensity score-matching analysis revealed that additional use of conventional clips was associated with a significantly reduced risk of delayed bleeding (P = 0.003). CONCLUSIONS: Additional use of conventional clips after prophylactic defect closure using OTSCs appears to be useful to reduce the risk of delayed bleeding after ER of SNADETs. UMIN Clinical Trials (No. 000035478).

Endoscopic submucosal dissection for colorectal neoplasms in proximity or extending to a diverticulum.

BACKGROUND AND AIMS: At specialized facilities, endoscopic submucosal dissection (ESD) has currently been performed even for difficult cases such as tumors extending to a diverticulum that previously required surgery. This study aims to classify the type of lesion according to the degree of infiltration to a diverticulum and assessed the safety and efficacy of ESD for each type of lesion. METHODS: We retrospectively reviewed ESD for lesions at NTT Medical Center Tokyo between January 2014 and April 2019. Lesions were classified as follows: Type 1: lesions in contact with or within 3 mm of the edge of a diverticulum; Type 2: lesions that partially infiltrated into a diverticulum; and Type 3: lesions that infiltrated into and completely covered the diverticulum. Furthermore, ESD strategies were divided into A and B, which indicates that a lesion was resected separately from the diverticulum and along the entire diverticulum, respectively. The clinicopathological characteristics and clinical outcomes were analyzed according to the strategy. RESULTS: A total of 47 lesions satisfied inclusion criteria (19 Type 1, 12 Type 2, and 16 Type 3 lesions). 19 Type 1 and 8 Type 2 lesions were resected using Strategy A, while 4 Type 2 and 16 Type 3 lesions were resected using Strategy B. En bloc resection was achieved in all cases. In Strategy A, the R0 resection rate was 96.3% and the curative resection rate was 88.9%. On the contrary, in Strategy B, the R0 resection rate was 95.0% and the curative resection rate was 90.0%. In Strategy B, one of the patients developed post-operative bleeding that required endoscopic hemostasis; another patient developed delayed perforation that required emergency surgery. CONCLUSIONS: ESD for colorectal neoplasms in proximity or extending to a diverticulum is challenging, but this procedure can be a safe and effective therapeutic option.

Nanobubble technology to treat spinal cord ischemic injury.

Background: Spinal cord ischemic injury is a severe complication of aortic surgery. We hypothesized that cerebrospinal fluid (CSF) oxygenation with nanobubbles after reperfusion could ameliorate spinal cord ischemic injury. Methods: Twenty white Japanese rabbits were categorized into 4 groups of 5 rabbits each: sham group, with balloon catheter insertion into the aorta; ischemia group, with spinal cord ischemic injury by abdominal aortic occlusion; nonoxygenated group, with nonoxygenated artificial CSF irrigation after spinal cord ischemic injury; and oxygenated group, with oxygenated artificial CSF irrigation after spinal cord ischemic injury. At 48 hours after spinal cord ischemic injury, the modified Tarlov score to reflect hind limb movement was evaluated. The spinal cord was histopathologically examined by counting anterior horn cells, and microarray and quantitative reverse-transcription polymerase chain reaction (qRT-PCR) analyses were performed. Results: The oxygenated group showed improved neurologic function compared with the ischemia and nonoxygenated groups (P < .01 and P = .019, respectively). Anterior horn neuron prevention in the sham, nonoxygenated, and oxygenated groups was confirmed (mean modified Tarlov score: sham, 9.2 ± 1.9; nonoxygenated, 10.2 ± 2.2; oxygenated, 10.4 ± 2.2; ischemia, 2.7 ± 2.7). Microarray analysis identified 644 genes with twofold or greater increased signals between the ischemia and sham groups. Thirty-three genes related to inflammatory response were enriched among genes differentially expressed between the oxygenated and ischemia groups. Interleukin (IL)-6 and tumor necrosis factor (TNF) expression levels were significantly lower in the oxygenated group compared with the ischemia group, while qRT-PCR showed lower IL-6 and TNF expression levels in the oxygenated group compared with the ischemia group (P < .05). Conclusions: CSF oxygenation with nanobubbles after reperfusion can ameliorate spinal cord ischemic injury and suppress inflammatory responses in the spinal cord.

Skill-up study of systemic endoscopic examination technique using narrow band imaging of the head and neck region of patients with esophageal squamous cell carcinoma: Prospective multicenter study.

OBJECTIVE: To evaluate the usefulness of a training program on endoscopic head and neck surveillance for beginner endoscopists. METHODS: This prospective multicenter study included 13 beginner endoscopists from 10 institutions who received training in systematic observation techniques and diagnostic criteria, and the training involved hands-on learning. Between May 2016 and February 2017, enrolled patients with current or previously diagnosed esophageal squamous cell carcinomas underwent head and neck surveillance using narrow band imaging (NBI) endoscopy, and histologically confirmed head and neck squamous cell carcinoma (HNSCC) detection rates, endoscopic image quality, and examination times were compared before (group A) and after (group B) the training program. Maximum possible score for the endoscopic images was 30 points. RESULTS: A total of 330 patients, comprising 181 in group A and 149 in group B, were enrolled. Three patients with HNSCC were detected in group A (1.7%) and in group B (2.0%; P = 1.000). Mean ± standard deviation (SD) examination times were 157 ± 71 s and 174 ± 109 s in groups A and B, respectively, (P = 0.073). Mean ± SD scores of the endoscopic images were 25.04 ± 5.47 points and 27.01 ± 4.35 points in groups A and B, respectively, (P < 0.001). CONCLUSION: The HNSCC detection rate based on the use of NBI on patients with ESCC did not improve after the training program for beginner endoscopists; however, endoscopic image quality improved significantly after the training program.

Differential selective hypothermic intercostal artery perfusion: a new method to probe spinal cord perfusion during thoracoabdominal aortic aneurysm repair.

OBJECTIVE: To prevent paraplegia in patients undergoing thoracoabdominal aortic aneurysm repair, the importance of preoperative identification of the Adamkiewicz artery and reconstruction of critical intercostal artery have been advocated. Conversely, significance of collateral network for spinal cord perfusion has been recognized. We invented a new system consisting of a direct monitoring of cerebrospinal fluid temperature (CSFT) and differential selective hypothermic intercostal artery perfusion (D-HIAP). METHODS: After exposing a critical intercostal artery, a 10-mm prosthetic graft was anastomosed in an end to side fashion. A balloon-tipped catheter was inserted into the graft to perfuse with 15 °C blood. Neighboring intercostal arteries were also perfused in the same fashion. Serial monitoring of CSFT was performed. Between January 2011 and January 2015, D-HIAP was employed in 50 patients with Adamkiewicz artery that located within a reconstructed area. RESULTS: Significant CSFT drop was recorded after initiation of D-HIAP in 42 (84%) patients. Of those, 34 (68%) patients showed significantly lowered CSFT with D-HIAP into a single critical intercostal artery. Perfusion into plural intercostal arteries was necessary for CSFT drop in 2 cases (4%), and plural intercostal artery perfusion further enhanced CSFT drop that had been modestly achieved by single intercostal artery perfusion in 6 cases (12%). Eight (16%) patients did not exhibit a significant drop in CSFT even when D-HIAP was employed for the critical and neighboring intercostal arteries. CONCLUSIONS: The detection of a disparity in temperature between the intrathecal space and blood generated by D-HIAP revealed individual variability in CSFT changes, which may imply a complexity in spinal cord perfusion. Intraoperative D-HIAP may help to identify a major blood supply for spinal cord perfusion and underlying collateral network.

Clinical Outcomes of Patients with Small Rectal Neuroendocrine Tumors Treated Using Endoscopic Submucosal Resection with a Ligation Device.

BACKGROUND/AIMS: The therapeutic strategies for small rectal neuroendocrine tumors (NETs) have not been standardized. We examined the efficacy and safety of endoscopic submucosal resection with a ligation device (ESMR-L) and the long-term outcomes after endoscopic treatment. METHODS: A total of 181 patients with rectal NETs <10 mm who were treated between May 2002 and May 2017 were retrospectively enrolled. All the lesions had been resected using ESMR-L, and the follow-up strategies were determined according to the pathological examinations. The long-term outcomes after a 53-month follow-up period were also evaluated. RESULTS: R0 resection was achieved in 180 cases (99.4%). Lymphovascular invasion was confirmed in 67 cases (37.0%), while a curative resection was achieved in 114 cases (63.0%). One perforation (0.6%) and 11 cases with delayed bleeding (6.1%) were observed. A multivariate logistic regression analysis revealed that a tumor size > 5 mm (OR 2.06; 95% CI 1.04-4.08, p = 0.04) was a significant independent predictor of the presence of lymphovascular invasion. Of the 67 patients with non-curative resections, 11 patients underwent additional surgery; lymph node metastasis was confirmed in 2 cases (18.2%). No local or distant metastases were observed during the follow-up period in 77 patients with a curative resection, 9 patients who received additional surgery, and 50 patients with non-curative resections. CONCLUSION: ESMR-L is an easy, safe and effective treatment for rectal NETs <10 mm in diameter, and the prognosis of patients seems to be good, despite a relatively high rate of lymphovascular invasion.

Hemodialysis is a strong risk factor for post-endoscopic sphincterotomy bleeding in patients with choledocholithiasis.

BACKGROUND AND STUDY AIMS: Hemodialysis (HD) is considered one of the risk factors for post-endoscopic sphincterotomy (ES) bleeding. Therefore, we conducted a retrospective study to evaluate HD as a risk factor for post-ES bleeding in patients with choledocholithiasis. PATIENTS AND METHODS: We used the post-ES bleeding rate as the main outcome measure. To evaluate the influence of HD on the risk of post-ES bleeding, logistic regression and propensity score analyses were conducted. In addition, univariate analysis-based comparisons of various clinical parameters (as secondary outcome measures) were performed between the patients in the HD and non-HD groups that experienced post-ES bleeding. RESULTS: A total of 1518 patients were enrolled. In the multivariate analysis, a platelet count of < 50,000, anticoagulant therapy, bleeding during ES, and HD were found to be significantly associated with post-ES bleeding (odds ratio [OR]: 35.30, 95 % confidence interval [CI]: 3.81 - 328.00; OR: 4.39, 95 % CI: 1.53 - 12.60; OR: 4.28, 95 % CI: 2.30 - 7.97; and OR: 13.30, 95 % CI: 5.78 - 30.80, respectively). Propensity score matching created 28 matched pairs. Propensity score analysis showed that the risk difference between the groups was 0.214 (95 % CI: 0.022 - 0.407). In a comparison between the patients in the HD and non-HD groups that suffered post-ES bleeding, it was found that the post-ES bleeding was significantly more severe in the HD group (p = 0.033), and massive blood transfusions and long periods of hospitalization were more frequently required in the HD group (p = 0.008 and p < 0.001, respectively). CONCLUSION: HD is an independent risk factor for post-ES bleeding and makes post-ES bleeding more serious.

Oxygenation of the cerebrospinal fluid with artificial cerebrospinal fluid can ameliorate a spinal cord ischemic injury in a rabbit model.

OBJECTIVE: We evaluated the effect of cerebrospinal fluid oxygenation for the prevention of spinal cord ischemic injury after infrarenal aortic occlusion in a rabbit model. METHODS: Twenty white Japanese rabbits were categorized into the following 4 groups (5 in each): group S (sham), balloon catheter insertion on to the aorta; group C (control), spinal cord ischemic injury by infrarenal abdominal aortic balloon occlusion for 15 minutes; group N (nonoxygenated), spinal cord ischemic injury with cerebrospinal fluid replacement by nonoxygenated artificial cerebrospinal fluid; and group O (oxygenated), spinal cord ischemic injury with cerebrospinal fluid replacement by nanobubble-oxygenated artificial cerebrospinal fluid. The changes in cerebrospinal fluid partial pressure of oxygen during the peri-ischemic period, modified Tarlov score, and histopathology of the spinal cord 48 hours after aortic maneuvers were evaluated. RESULTS: Cerebrospinal fluid partial pressure of oxygen significantly increased in group O compared with group N after cerebrospinal fluid replacement (254.5 ± 54.8 mm Hg vs 136.1 ± 43.5 mm Hg, P = .02). After 15 minutes of spinal cord ischemic injury, cerebrospinal fluid partial pressure of oxygen in group C decreased to 65.8 ± 18.6 mm Hg compared with baseline (148.8 ± 20.6 mm Hg, P < .01), whereas cerebrospinal fluid partial pressure of oxygen in group O was maintained at remarkably high levels after spinal cord ischemic injury (291.9 ± 51.8 mm Hg), which was associated with improved neurologic function, with 20% of spinal cord ischemic injury having a Tarlov score less than 5 compared with 100% of spinal cord ischemic injury in group C. Preservation of anterior horn neurons in groups N and O was confirmed by histopathologic analysis with significant reduction of degenerated neurons compared with group C. CONCLUSIONS: Cerebrospinal fluid oxygenation with artificial cerebrospinal fluid can exert a protective effect against spinal cord ischemic injury in rabbits.

Modification of a Standard Thoracoabdominal Incision to Preserve Collaterals to Adamkiewicz Artery.

We report a case of a 35-year-old male who underwent thoracoabdominal aortic repair of a chronic dissecting aortic aneurysm, Crawford extent II. Preoperative computed tomography showed thrombosis of almost all intercostal arteries. Precise diagnostic assessment demonstrated the Adamkiewicz artery originating from the left lateral thoracic artery and subscapular artery, which would have been at risk after using a standard Stoney's incision, thus potentially causing paraplegia or paraparesis due to spinal cord ischemia. We modified the lateral thoracic incision anteriorly and successfully preserved the collateral arteries without impairing the spinal cord function.

[Issues in Coronary Artery Bypass Grafting for Kawasaki Disease].

Progressive narrowing at the entrance and exit of coronary artery aneurysm can develop at late phase of Kawasaki disease (KD). Evaluation and prediction of progressive coronary lesions remain a challenge in the treatment of post-KD coronary artery disease. We aimed to elucidate long-standing issues imposed on the patients who underwent coronary artry bypass grafting (CABG) for coronary artery lesions associated with KD. Between January, 2000 and December, 2013, CABG for coronary artery lesions associated with KD were performed in 6 patients (male/female: 5/1, mean age 14.5±10.0). There was no operative mortality. Follow-up for the 6 patients has been performed with the average period of 5 years (1~9 years). Cardiac events occurred in 2 patients during follow-up. In 1 patient, left internal thoracic artery (LITA) occluded due to flow competition between the native artery and LITA graft after LITA to LAD bypass grafting. The other patient required a re-do CABG using the free right internal thoracic artery to the circumflex branch because of occlusion at the coronary artery aneurysms after 4 years postoperatively. Meticulous preoperative diagnostic evaluations of coronary artery aneurysm may further improve the long-term outcome after surgical intervention for coronary lesions in conjunction with an aneurysm.

[Preoperative Use of Tolvaptan in a Patient with Constrictive Pericarditis].

Tolvaptan is a new selective vasopression V2-receptor antagonist. We report our experience with a use of tolvaptan for preoperative fluid management in a patient with severe constrictive pericarditis. A 66-year-old man presented with heart failure symptoms derived from constrictive pericarditis. Chest X-ray showed right pleural effusion and chest computed tomography demonstrated severe pericardial calcification. Despite that he received optimal conventional medical treatments, his hemodynamic condition further exacerbated during hospitalization. We administered tolvaptan in an attempt to optimize preoperative fluid management. Tolvaptan was found to be remarkably effective in that regard. The body weight decreased and the heart failure symptoms improved. Pericardiectomy was performed successfully, and he recovered uneventfully.

Coronary artery bypass grafting in a patient with hemophilia B: continuous recombinant factor IX infusion as per the Japanese guidelines for replacement therapy.

We herein report our experience of successfully managing the hemostatic system by controlling serum factor IX levels throughout the perioperative period in a patient with hemophilia B. Coronary artery bypass grafting with cardiopulmonary bypass was planned for a 52-year-old man with moderate severity of hemophilia B. During surgery, recombinant factor IX (rFIX; BeneFIX(®) Pfizer Japan inc., Tokyo, Japan) was administered by bolus infusion followed by continuous infusion as per the guidelines of the Japanese Society on Thrombosis and Hemostasis. The operative course was uneventful without any considerable bleeding or complications.

[Early Postoperative Outcomes and Evaluation of Hemodynamics after Mitral Valve Replacement with Epic Mitral Bioprosthesis].

BACKGROUND: In Guideline for Surgical and Interventional Treatment of Valvular Heart Disease, revised by Japanese Circulation Society in 2012, mitral valve replacement (MVR) with bioprosthesis is class II b recommendation for patients aged 70 years or older who have no risk factors for thromboembolism. The aim of this study was to evaluate the early postoperative surgical outcomes and the hemodynamic performance with the Epic mitral bioprosthesis. METHODS: Twenty-six consecutive patients underwent MVR with Epic mitral bioprostesis at Tohoku University Hospital between April 2011 and July 2014. Twenty-five cases of 26 were evaluated their hemodynamics at discharge, and of which 19 cases of 26 were evaluated at the outpatient clinic during follow-up period. RESULTS: There was 1 hospital death. Long-term mortality or reoperation for any valve abnormality was not observed in the median follow-up of 23.9 ± 11.3 months. Hemodynamic date at discharge obtained by transthoracic echocardiography included mean hemodynamics of mitral valve bioprosthesis as below. Effective orifice area (EOA):2.44 ± 0.62 cm², peak mitral pressure gradient (pMPG):15.8 ± 5.3 mmHg, mean mitral pressure gradient(mMPG):7.2 ± 2.4 mmHg. Hemodynamic parameters at follow-up were found to be stable as EOA:2.25 ± 0.64 cm², pMPG:17.3 ± 5.7 mmHg, mMPG:6.2 ± 2.3 mmHg, respectively. CONCLUSION: We have attempted to elucidate our preliminary postoperative outcomes and hemodynamics after MVR with Epic mitral bioprosthesis. These in vivo hemodynamic data can serves a clinical reference.

[Anastomotic Pseudoaneurysm after Aortic Root Replacement].

Aortic root replacement has been an established standard procedure to treat annuloaortic ectasia (AAE) or aortic root aneurysm associated with significant aortic valvular disease. The long-term outcome after the surgery has also been favorably reported;however, an occurrence of anastomotic pseudoaneurysm remains a dreadful and serious complication. Detection of asymptomatic pseudoaneurysm used to be a challenge, because conventional computed tomography (CT) scan often fails to reveal a presence of pseudoaneurysm formation mainly due to remarkable artifact from prosthetic valve or motion effect. Recent advance in electrocardiogram (ECG)-gated 3-dimentional (3D)-CT has led to visualize even a small pseudoaneurysm and delineate an exact origin of a pseudoaneurysm. This powerful diagnostic modality enables us to precisely plan therapeutic strategy to accomplish efficacious surgical repair or interventional radiological treatment when possible.

[Leg amputation for severe lower limb ischemia caused by type A acute aortic dissection; report of a case].

A 41-year-old man underwent total arch replacement and aorto-bifemoral bypass owing to type A acute aortic dissection complicated by ischemia of both lower extremities. Just after the operation, he developed myonephropathic metabolic syndrome due to severe ischemia of the right leg, and hemodiafiltration was performed. However, the serum potassium was elevated to an uncontrollable level. Ligation of the right femoral artery and the right branch of the bypass graft was performed one hour after the transfer to intensive care unit (ICU), and the serum potassium dropped to a normal level. He underwent amputation of the right lower limb above the knee on the 13th postoperative day, and was discharged after long-term rehabilitation.

Application of a phosphite dehydrogenase gene as a novel dominant selection marker for yeasts.

The use of antibiotic resistance markers in the commercial application of genetically modified microorganisms is limited due to restrictions on the release of antibiotics and their resistance genes to the environment. To avoid contamination by other microorganisms, the development of a dominant selection marker with low environmental risks is still needed. Here we demonstrated a new selection system for Schizosaccharomyces pombe and Saccharomyces cerevisiae using a bacterial phosphite dehydrogenase gene (ptxD). A Sz. pombe transformant carrying ptxD under a strong promoter or on a multicopy plasmid grew on a minimal medium containing phosphite (Pt) as a sole source of phosphorus. To adapt this system to S. cerevisiae strains, codon optimization of ptxD was necessary. The codon-optimized ptxD system appeared effective in not only laboratorial but also industrial S. cerevisiae strains that are diploid or polyploid. Since Pt is a safe and inexpensive chemical, ptxD could be used as a novel dominant selection marker applicable on an industrial scale.